Yeah, I should clarify a bit about what I said. There are numerous ace cutting routines out there in the literature. It's just that Scarne's aces claims to be the ultimate in such routines.
The conditions that are usually given for Scarne's aces are really stringent ones (borrowed deck, shuffled by a spectator, no crimps or preparation, performer just shuffles a few times after the spectators and cuts to aces without hesitation). It is a really hard trick with all these conditions and Bill Malone's exhibition is the only one I have seen which appears to satisfy these conditions.
Somehow Scarne's explanation, which Bill Malone also gives in his performance doesn't seem right or even humanly possible (locating aces in mid shuffle and then counting how many cards are put above it is just insanely hard). I am open to being proved wrong, but I suspect the method Bill Malone used is something very different.
There is also the story by Vernon about his encounter with Stevens, the man who invented the Stevens Cull. From what I've heard, the Stevens Cull should enable you to perform Scarne's aces in its true "mythical" sense, but that is another story altogether.